See the California gender pay gap by occupation

Full-time, California female workers in their 30s make about 84 cents for every dollar earned by their male counterparts in the same age bracket, according to a Bee review of census data.

The strongest equal pay law in the nation went into effect in California at the start of 2016. The bill broadens existing law and says that women must be paid the same for doing “substantially similar” work. Employers, in the case of lawsuits, would have to prove they were paying a male worker more for “legitimate” reasons, such as seniority or merit.

The challenge of closing the gap will be significant.

The Bee looked at earnings for more than two dozen occupations with the highest number of male and female California workers. It restricted its analysis to men and women in their 30s who worked at least 35 hours a week to compare people at similar points in their careers.

The census data, which covered a five-year period between 2008 and 2012, showed gender pay gaps in all but two occupations - registered nurses and high school teachers. The gaps for college professors and elementary teachers were small.

The largest gaps were among real estate agents, janitors, accountants, agricultural workers and financial managers. Women in those occupations made less than 75 cents on the dollar annually compared to their male counterparts.

The causes of the gender pay gap in California and elsewhere are controversial. Some point to maternity leave interrupting a women's career or to fewer hours worked by women than men. (California men in The Bee's analysis worked an average of 44.4 hours per week; women worked an average of 42.2 hours per week.) "However," write Cornell professors Francine Blau and Lawrence Kahn, "even controlling for experience and whatever other qualifications that can readily be measured, there tends to be a pay difference between men and women that is not explained and is potentially due to discrimination."

Source: U.S. Census Bureau, American Community Survey, 2008-2012 | Notes: The Census Bureau "top codes" salaries above roughly $500,000. These salaries represent about two-tenths of 1 percent of the salaries in the analysis. Excludes workers who reported no earnings. Click here to see chart if using The Bee's mobile app.

Gov. Jerry Brown applauds female factory workers from World War II as he visits the Rosie the Riveter National Monument in Richmond to sign an equal-pay law on Oct. 6. Kristopher SkinnerBay Area News Group

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